Piton de La Fournaise - overflight of the eruptive site by the PGHM on 05.04.2020: lava fountain 50 m high. and rapid construction of a cone - photo SAG and PGHM via OVPF
Following a reconnaissance flight by the SAG and the PGHM carried out on April 5 at around 10:30 am local time at Piton de La Fournaise, the casting front could be located with precision (white star on the map). It was 550 m above sea level, about 2.7 km from national road 2 (compared to 800 m above sea level and 3 km from the road yesterday at 6:52 pm). The activity focuses on 2-3 eruptive mouths, with lava fountains reaching 50 meters high.
Note that from an altitude of 400m the slopes will be much less steep (12-13% on average) which will have the consequence of slowing the spread of the flow.
Piton de La Fournaise - Mapping of the lava flow dated 4/4/2020 at 18:52 local time. The white star represents the position of the pouring front at 10:12 local time on 5/4/2020 (© OVPF / IPGP / LMV / OPGV).
The intensity of the volcanic tremor (indicator of the intensity of the eruption) has been relatively stable over the past 24 hours.
Strong seismic activity has been recorded under the summit craters since morning, and 189 superficial volcano-tectonic earthquakes have been recorded. These earthquakes are located less than 2 km deep below the southeast edge of the summit.
These earthquakes testify to the weakening of the environment, either by a circulation of fluid or the emptying of a reservoir, most certainly in connection with the supply of the eruptive site and its revival of activity since approximately 24 hours.
Given this weakening, a risk of collapse of the Dolomieu crater (or part of the crater) is not excluded.
Piton de La Fournaise- Evolution of the RSAM (volcanic tremor indicator) since 02/04/2020 at 00h UT time (04h local time) on the seismological station DSO located at the top of the volcano. (© OVPF / IPGP).
Piton de La Fournaise - Histogram representing the number of surface volcano-tectonic earthquakes recorded since 4/4/2020 00 (UT time).
Thermal images taken by an OVPF team yesterday evening and images from OVPF webcams that night show that the pour is still very active. Last night, the OVPF team on site reported that the northernmost casting fronts had stopped, with activity focusing on a new casting arm to the south. The lava front on this new arm most certainly progressed last night. The Sainte Rose gendarmerie will go on site to regularly monitor its development, given the increase in lava flows.
The estimated surface flows, from satellite data via the HOTVOLC (OPGC - University of Auvergne) and MIROVA (University of Turin) platforms, although still greatly disturbed by the cloud cover around Piton de la Fournaise, are still within the rise. Over the past 12 hours, average flows have been estimated at 30 m³ / s.
Thermal anomalies, when not disturbed by cloud cover, are very high, with a VRP of 5,218 MW on April 5 at 6:55 p.m.
Piton de La Fournaise - Shooting of the eruptive site on 5/4/2020 around 8pm local time from the RN2 - note the temperature difference between the two lava arms (© OVPF-IPGP).
Piton de La Fournaise - SO2 mass 5,66 kt on 05.04.2020 - Doc. Sentinel-5 P Tropomi - DLR / BIRA / ESA
The Réunion air observatory (ORA) has recorded a concentration of sulfur dioxide (SO2) since Sunday, April 5, 2020 since 5 am in the town of Tampon (observation station "Bourg Murat"). Consequently, the prefect of Réunion decided to implement the information and recommendation procedure relating to atmospheric pollution.
Short-term exposure may have limited and transient health effects for sensitive people such as young children, asthma or allergies, chronic respiratory failure or the elderly with respiratory disorders, over 65 years and women pregnant.
Weather news draws attention to the dispersion of Pélé's hair over an area up to 50 km from the eruption site, e.g. on the Plaine des Palmistes, Bras Panon, etc.
Sources: OVPF, ORA, Weather news 974 & Ludovic Leduc / Onactif volcans
Find all the information relating to the activity of Piton de la Fournaise on the various media of the OVPF-IPGP:
- the website (http://www.ipgp.fr/fr/ovpf/actualites-ovpf),
- the Twitter account (https://twitter.com/obsfournaise?lang=fr),
- and the facebook account (https://www.facebook.com/ObsVolcanoPitonFournaise/)
In the Ryukyu arc, the activity of the Kuchinoerabujima continues, according to the JMA with plumes of gas and ash observed this April 6 at 8:10 a.m. JST, from a height of 400 meters, and at 3 p.m. JST, with a plume reaching 700 meters.
Ash and lapilli falls are expected.
The alert level is 3 / do not approach the volcano.
Sources: JMA & NHK
On Suwanosejima, on alert level 2 / not to approach the crater, an eruption occurred on March 6 from 3 p.m. local time, and ash falls are expected.